The invention relates to a glow discharge source, in particular for the analysis of solid specimens by means of glow discharge, with an anode and a cathode and with means for the direct or indirect cooling of a specimen. Glow discharge sources are known, inter alia, in the form of ion sources for mass spectrometric analyses. In the glow discharge source, the surface of a specimen is removed and ionized by a plasma. The ions originating from the specimen are discharged from the source and fed to a mass spectrometer.
The solid specimen is heated up by the plasma. Cooling of the specimen is advantageous, to avoid melting. This applies in particular to thin specimens or systems of layers. A constant specimen temperature is also advantageous for the accuracy and reproducibility of the measurement results. Finally, the stability of the removal of the specimen surface sputter process is to be ensured.
In known devices, the cooling of the specimen takes place with the aid of water. In this case, only temperatures near freezing can be achieved without additives. For specimens with a low melting point, this is possibly not adequate, for example for gallium (Ga). With this type of cooling, the rate of temperature change is also low.
Finally, it is advantageous to be able to heat up the specimen after cooling to avoid condensation. This requires additional technical measures.